This book contains 150 brand NEW, previously UNPUBLISHED Jigsaw Sudoku puzzles and variants thereof.All in all, you get: Jigsaw (or irregularly shaped) Sudoku puzzles share the same rules with classic Sudoku. The only difference is that the nine nonets are, well, irregularly shaped.This makes the puzzles slightly harder than the original Sudoku and surely more entertaining, because every puzzle has a unique nonet design and therefore, they can never become boring